Age-old clashes between fathers and sons are the rusty engine parts that drive "Jayne Mansfield's Car," a wheezy, schematic ensembler centered around two families in 1969 Alabama.

Age-old clashes between fathers and sons are the rusty engine parts that drive “Jayne Mansfield’s Car,” a wheezy, schematic ensembler centered around two families in 1969 Alabama. Billy Bob Thornton’s first writing-directing effort in more than a decade aspires to be a vintage piece of down-home storytelling replete with culture-clash comedy, dysfunctional angst and an overarching theme about shifting Vietnam-era attitudes toward the heroism of war. But a fine cast can only do so much with the script’s pileup of generational conflict and long-winded introspection, resulting in a willfully out-of-step picture that will struggle to connect with an audience.

In line with some of Thornton’s earlier films, this largely Russian-financed yet thoroughly American feature is steeped in the language and atmosphere of the rural South; its characters’ tendency to speak in soulful anecdotes and monologues reps an unabashed throwback to a mostly bygone literary and cinematic tradition. Arriving in an era of widespread disenchantment with U.S. involvement in conflicts overseas, however, there’s something unavoidably retrograde about a late-’60s period piece whose primary purpose is to dispel any lingering temptation auds might feel to view the horrors of war through a romantic or nostalgic prism.

Vexingly, this notion provides not only the subtext but the chief structuring device of Thornton’s screenplay (written with Tom Epperson, his scripting partner on “One False Move” and “A Family Thing”), which was drafted for the screen but at times feels as if it were adapted from a pre-existing novel or sub-Tennessee Williams play. Adding to the film’s overly studied quality is the title, a reference to the 1967 car accident that killed Mansfield and became a morbid pop-cultural touchstone, which serves here as a belabored metaphor for the American impulse to glamorize death.

No one onscreen is more guilty of this than crusty patriarch Jim Caldwell (Robert Duvall), a WWI veteran who has raised his four children in the town of Morrison, Ala. Two of them, Skip (Thornton) and Carroll (Kevin Bacon), served valiantly in WWII but have mixed feelings about their experiences; Carroll is now an LSD-using hippie and Vietnam protest leader, while the more reserved Skip professes a mild taste for “underground music.” In the sort of overly tidy irony that will prove characteristic throughout, their brother Jimbo (Robert Patrick), the only Caldwell boy who didn’t go to war, shares his father’s rah-rah military zeal.

Things are set in motion when Jim learns that his ex-wife and the mother of his children has died in the U.K. Even worse, she requested that her body be buried back in Morrison, and her second husband, Kingsley Bedford (John Hurt), is traveling from England with his own grown kids, Phillip (Ray Stevenson) and Camilla (Frances O’Connor), to attend the funeral. Jim’s daughter, blonde beauty Donna (Katherine LaNasa), has the bright idea of inviting the Bedfords over for dinner and having the two rival clans meet at long last.

Yet apart from a few easy, stereotypical jabs about the Brits’ foul weather and even fouler food, the anticipated feud between the wronged Caldwells and the home-wrecking Bedfords never materializes. If anything, the families hit it off too well: Donna puts the moves on the handsome Phillip, while Skip asks the fetching Camilla to participate in his bizarre sexual fantasies; this builds unexpectedly to the film’s strongest sequence, in which Skip poignantly reveals the full extent of his war scars, physical and emotional.

The point seems to be that strife between families is nothing compared with each family’s own internal father-son enmity. The undoing of “Jayne Mansfield’s Car” is that this discord expresses itself, with lumbering repetitiveness, through the characters’ arguments about their war records or lack thereof. Jim hates Carroll’s anti-war stance; Skip and Carroll resent Jim for not appreciating their efforts to follow in his footsteps; least plausibly of all, even Kingsley has an ax to grind over Phillip’s WWII service. All these simmering tensions come to a head on a dark and stormy night at the Caldwell estate marked by one candlelit confrontation after another, cloaked in such squint-inducing shadows that the lensing seems to be paying homage to mid-’70s Gordon Willis.

From an acting standpoint, a crucial flaw is that the core ensemble never plausibly coheres as a family; a late scene with Thornton’s Skip, Patrick’s Jimbo and Bacon’s Carroll smoking together outdoors points up this fundamental disconnect. Duvall comes off best in show, tearing into his old-coot role with relish and striking up a nice, curmudgeonly rapport with Hurt. By contrast, the excellent LaNasa and O’Connor feel limited by the fact that, in this male-weepie context, the women exist merely to listen to the men and appease them sexually, not always in that order.

Georgia-lensed production boasts a rich sense of place abetted by a twangy score and period-appropriate soundtrack. Some tightening would improve the picture before release; the final scene in particular reps a prime candidate for excision.